Psychometric properties of the malay-translated eight-item electronic cigarette dependence scale (EDS-8) among electronic cigarette users in Malaysia

INTRODUCTION: The popularity of e-cigarettes is increasing globally. Validated instruments in local languages are needed to measure e-cigarette dependence for surveillance, diagnosis, and treatment of e-cigarette dependence. We assessed the psychometric properties of the Malay language version of the 8-item e-cigarette Dependence Scale, EDS-8(Malay), among exclusive e-cigarette users. METHODS: The original English version of the eight-item e-cigarette Dependence Scale (EDS-8) was translated into Malay to suit the local context by standard forward and backward translation methods. Two professional native Malay-speaking translators and two professional native English-speaking translators carried out the forward and backward translation process, respectively. The reliability and validity of the EDS-8 (Malay) were determined using a group of 251 adult Malaysians who were exclusive e-cigarette users. They were recruited from social media platforms. RESULTS: Their mean age was 37.9 (SD = 10.3) years, and 73.2% were males, Malay race (41.3%), attained secondary education (51.8%), were employed (88.4%), and 61.7% were frequent vapers. Cronbach's alpha of EDS-8 (Malay) was 0.894. Corrected item-total correlations were greater than 0.4. The EDS-8 (Malay) displayed a good composite reliability of 0.896. A confirmatory factor analysis revealed that the one-factor model exhibited good fit indices, including root mean squared error of approximation (0.056), goodness-of-fit index (0.967), adjusted goodness-of-fit index (0.935), comparative fit index (0.984), and non-normed fit index (0.975). EDS-8 (Malay) was able to detect the between-group mean differences as shown by higher scores among e-cigarette users who were Indians, had lower income, received secondary education, and vaped regularly. CONCLUSIONS: The instrument EDS-8 (Malay) displayed acceptable reliability, content, and construct validity. The convergent validity of EDS-8 (Malay) should be tested when comparable tools become available in the Malay language. IMPLICATIONS: To date, there are no validated translated versions of e-cigarette dependence tools originally developed in the English language. Our Malay language version of the eight-item e-cigarette dependence scale provides locally validated e-cigarette dependence for potential use in Malaysian clinical settings and for research on e-cigarette addiction. The other tools available for the assessment of e-cigarettes need to be translated and validated to assess the convergent validity of the eight-item e-cigarette dependence scale in the Malay language.